Record Rain Predicted in the 100-Year Forecast

It’s going to rain.  According to a study by climatologists at the University of Illinois at Urbana-Champaign and Texas Tech University, temperatures in Chicago will continue rising over the next century, largely due to human emissions of heat-trapping gasses.  The strength of that warming trend and the impact it brings depends on the amount of future emissions produced by the city and the world.  Katharine Hayhoe, a research associate professor in Texas Tech’s Department of Geosciences, co-led the team of more than 20 researchers along with Donald Wuebbles, professor of atmospheric sciences at the University of Illinois.

Rains of more than 2 ½ inches a day, an amount that can activate sewage overflows into Lake Michigan, are expected to rise by 50 percent between now and 2039.  By the end of the century, the number of big storms could jump by an almost unbelievable 160 percent.  “We’ve already seen an increase in these extreme weather events, especially in the Midwest and Northeast,” said Don Wuebbles, a U. of I. climatologist who co-authored the study.  “Chicago has had two 100-year storms in three years.  Iowa has had three 100-year floods in less than 20 years.  That’s telling us something.”

Researchers studying Milwaukee’s sewer system concluded that heavy rains caused by climate change could equal a 20 percent increase in the number of sewage overflows, a disturbing sign for Chicago, Cleveland, Detroit and other Midwestern industrial cities with similar systems.  As new research points to a changing climate — including heaver rains punctuated by periods of drought — Chicago officials are struggling with the likelihood that the city will need solutions other than the $3 billion Deep Tunnel, an underground network of giant sewer pipes and reservoirs that won’t be completed until 2029.  “There is no doubt that things are going to get tougher,” said Marcelo Garcia, a U. of I. hydrological engineer who is studying Deep Tunnel’s effectiveness.  “I like to think of the entire system as a giant bathtub.  They built a really big bathtub to collect all this water, but it turns out it isn’t nearly as big as what they need.”

But Chicago needs to do more, said Thomas Cmar, an attorney in the Chicago office of the Natural Resources Defense Council. “Every time the city tears up a street for improvements, they should be thinking about porous pavement in the parking lanes and street trees and rain gardens,” he said. “These things don’t require a lot of money upfront but can pay huge dividends down the line.”

The majority of climate scientists agree that rising global temperatures are changing rain patterns because of increased evaporation and more moisture in the air.  They are less certain about how fast climate change is happening and how human disruption of natural climate cycles affects day-to-day weather.

Another report from the National Wildlife Federation (NWF) concurs. More Extreme Weather and the U.S. Energy Infrastructure, The study details National Wildlife Federation how severe droughts, heavier rainfall events, changing snowmelt, and more intense tropical storms may cause significant disruptions to the nation’s energy grid, all while the existing system calls for upgrades. “Our hospitals, homes, and economy depend on an energy infrastructure that will be increasingly disrupted by extreme weather events related to climate change,” said Amanda Staudt, Ph.D., a NWF climate scientist and the report’s author.